STM32F302 差分ADC异常，采集跳动
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_GPIOA | RCC_AHBPeriph_GPIOC | RCC_AHBPeriph_GPIOF, ENABLE);GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_2 | GPIO_Pin_3
| GPIO_Pin_4 | GPIO_Pin_5 | GPIO_Pin_6 | GPIO_Pin_7 ;
GPIO_InitStructure.GPIO_Mode = GPIO_Mode_AN;
GPIO_InitStructure.GPIO_PuPd = GPIO_PuPd_NOPULL ;
GPIO_Init(GPIOA, &GPIO_InitStructure);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_0 | GPIO_Pin_1 | GPIO_Pin_2 | GPIO_Pin_3 | GPIO_Pin_4;
GPIO_Init(GPIOC, &GPIO_InitStructure);
GPIO_InitStructure.GPIO_Pin = GPIO_Pin_2 | GPIO_Pin_4;
GPIO_Init(GPIOF, &GPIO_InitStructure);
//ADC Init
RCC_ADCCLKConfig(RCC_ADC12PLLCLK_Div1);
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_ADC12, ENABLE);
ADC_StructInit(&ADC_InitStructure);
/* Calibration procedure */
ADC_VoltageRegulatorCmd(ADC1, ENABLE);
ADC_VoltageRegulatorCmd(ADC2, ENABLE);
vTaskDelay(10);
ADC_SelectCalibrationMode(ADC1, ADC_CalibrationMode_Differential);
ADC_StartCalibration(ADC1);
ADC_SelectCalibrationMode(ADC2, ADC_CalibrationMode_Differential);
ADC_StartCalibration(ADC2);
while(ADC_GetCalibrationStatus(ADC1) != RESET );
calibration_value1 = ADC_GetCalibrationValue(ADC1);
while(ADC_GetCalibrationStatus(ADC2) != RESET );
calibration_value2 = ADC_GetCalibrationValue(ADC2);
/* ADC Dual mode configuration */
ADC_CommonInitStructure.ADC_Mode = ADC_Mode_RegSimul;
ADC_CommonInitStructure.ADC_Clock = ADC_Clock_AsynClkMode;
ADC_CommonInitStructure.ADC_DMAAccessMode = ADC_DMAAccessMode_1;
ADC_CommonInitStructure.ADC_DMAMode = ADC_DMAMode_Circular;
ADC_CommonInitStructure.ADC_TwoSamplingDelay = 10;
ADC_CommonInit(ADC1, &ADC_CommonInitStructure);
/* */
ADC_InitStructure.ADC_ContinuousConvMode = ADC_ContinuousConvMode_Disable;//ADC_ContinuousConvMode_Enable;
ADC_InitStructure.ADC_Resolution = ADC_Resolution_12b;
ADC_InitStructure.ADC_ExternalTrigConvEvent = ADC_ExternalTrigConvEvent_5;//Event5 = TIM4_CC4 event Event12 = TIM4_TROG event
ADC_InitStructure.ADC_ExternalTrigEventEdge = ADC_ExternalTrigEventEdge_RisingEdge;
ADC_InitStructure.ADC_DataAlign = ADC_DataAlign_Right;
ADC_InitStructure.ADC_OverrunMode = ADC_OverrunMode_Disable;
ADC_InitStructure.ADC_AutoInjMode = ADC_AutoInjec_Disable;
ADC_InitStructure.ADC_NbrOfRegChannel = 4;
ADC_Init(ADC1, &ADC_InitStructure);
ADC_InitStructure.ADC_ExternalTrigEventEdge = ADC_ExternalTrigEventEdge_None;
ADC_Init(ADC2, &ADC_InitStructure);
/* ADC1 regular channel7 and channel8 configuration */
ADC_RegularChannelConfig(ADC1, ADC_Channel_1, 1, ADC_SampleTime_61Cycles5);
ADC_RegularChannelConfig(ADC1, ADC_Channel_2, 2, ADC_SampleTime_61Cycles5);
ADC_RegularChannelConfig(ADC1, ADC_Channel_3, 3, ADC_SampleTime_61Cycles5);
ADC_RegularChannelConfig(ADC1, ADC_Channel_4, 4, ADC_SampleTime_61Cycles5);
ADC_RegularChannelConfig(ADC1, ADC_Channel_5, 5, ADC_SampleTime_61Cycles5);
ADC_RegularChannelConfig(ADC1, ADC_Channel_6, 6, ADC_SampleTime_61Cycles5);//与ADC2共用CH6,错时使用
ADC_RegularChannelConfig(ADC1, ADC_Channel_7, 7, ADC_SampleTime_61Cycles5);
ADC_RegularChannelConfig(ADC1, ADC_Channel_8, 8, ADC_SampleTime_61Cycles5);
ADC_RegularChannelConfig(ADC2, ADC_Channel_1, 1, ADC_SampleTime_61Cycles5);
ADC_RegularChannelConfig(ADC2, ADC_Channel_2, 2, ADC_SampleTime_61Cycles5);
ADC_RegularChannelConfig(ADC2, ADC_Channel_3, 3, ADC_SampleTime_61Cycles5);
ADC_RegularChannelConfig(ADC2, ADC_Channel_4, 4, ADC_SampleTime_61Cycles5);
ADC_RegularChannelConfig(ADC2, ADC_Channel_9, 5, ADC_SampleTime_61Cycles5);
ADC_RegularChannelConfig(ADC2, ADC_Channel_10, 6, ADC_SampleTime_61Cycles5);
ADC_RegularChannelConfig(ADC2, ADC_Channel_5, 7, ADC_SampleTime_61Cycles5);
ADC_RegularChannelConfig(ADC2, ADC_Channel_6, 8, ADC_SampleTime_61Cycles5);//与ADC1共用CH6,错时使用
ADC_SelectDifferentialMode(ADC1, ADC_Channel_1, ENABLE); //差分通道
ADC_SelectDifferentialMode(ADC1, ADC_Channel_3, ENABLE);
ADC_SelectDifferentialMode(ADC1, ADC_Channel_5, ENABLE);
ADC_SelectDifferentialMode(ADC1, ADC_Channel_7, ENABLE);
ADC_SelectDifferentialMode(ADC2, ADC_Channel_1, ENABLE); //差分通道
ADC_SelectDifferentialMode(ADC2, ADC_Channel_3, ENABLE);
ADC_SelectDifferentialMode(ADC2, ADC_Channel_9, ENABLE);
ADC_SelectDifferentialMode(ADC2, ADC_Channel_5, ENABLE);
/* Configures the ADC DMA */
ADC_DMAConfig(ADC1, ADC_DMAMode_Circular);
/* Enable the ADC DMA */
ADC_DMACmd(ADC1, ENABLE);
/* Enable ADC1 and ADC2 */
ADC_Cmd(ADC1, ENABLE);
ADC_Cmd(ADC2, ENABLE);
/* wait for ADC1 ADRDY */
while(!ADC_GetFlagStatus(ADC1, ADC_FLAG_RDY));
/* wait for ADC2 ADRDY */
while(!ADC_GetFlagStatus(ADC2, ADC_FLAG_RDY));
vTaskDelay(10);
//DMA Init
RCC_AHBPeriphClockCmd(RCC_AHBPeriph_DMA1, ENABLE);
DMA_InitStructure.DMA_PeripheralBaseAddr = ADC_CDR_ADDRESS;
DMA_InitStructure.DMA_MemoryBaseAddr = (uint32_t)&ADCDualConvertedValue;
DMA_InitStructure.DMA_DIR = DMA_DIR_PeripheralSRC;
DMA_InitStructure.DMA_BufferSize = 300*4;
DMA_InitStructure.DMA_PeripheralInc = DMA_PeripheralInc_Disable;
DMA_InitStructure.DMA_MemoryInc = DMA_MemoryInc_Enable;
DMA_InitStructure.DMA_PeripheralDataSize = DMA_PeripheralDataSize_Word;
DMA_InitStructure.DMA_MemoryDataSize = DMA_MemoryDataSize_Word;
DMA_InitStructure.DMA_Mode = DMA_Mode_Circular;
DMA_InitStructure.DMA_Priority = DMA_Priority_Medium;
DMA_InitStructure.DMA_M2M = DMA_M2M_Disable;
DMA_Init(DMA1_Channel1, &DMA_InitStructure);
NVIC_PriorityGroupConfig(NVIC_PriorityGroup_1);
NVIC_InitStructure.NVIC_IRQChannel = DMA1_Channel1_IRQn;
NVIC_InitStructure.NVIC_IRQChannelPreemptionPriority = 0x0;
NVIC_InitStructure.NVIC_IRQChannelSubPriority = 0x0;
NVIC_InitStructure.NVIC_IRQChannelCmd = ENABLE;
NVIC_Init(&NVIC_InitStructure);
DMA_ITConfig(DMA1_Channel1, DMA_IT_TC, ENABLE);
DMA_Cmd(DMA1_Channel1, ENABLE);
//TIM4 Init
RCC_APB1PeriphClockCmd(RCC_APB1Periph_TIM4, ENABLE);
/* TIM4 configuration ------------------------------------------------------*/
/* Time Base configuration */
TIM_TimeBaseStructInit(&TIM_TimeBaseStructure);
TIM_TimeBaseStructure.TIM_Period = 24000-1; //72M/3K = 24K
TIM_TimeBaseStructure.TIM_Prescaler = 0;
TIM_TimeBaseStructure.TIM_ClockDivision = 0x0;
TIM_TimeBaseStructure.TIM_CounterMode = TIM_CounterMode_Up;
TIM_TimeBaseInit(TIM4, &TIM_TimeBaseStructure);
/* TIM4 channel1 configuration in PWM mode */
TIM_OCInitStructure.TIM_OCMode = TIM_OCMode_PWM2;
TIM_OCInitStructure.TIM_OutputState = TIM_OutputState_Enable;
TIM_OCInitStructure.TIM_OutputNState = TIM_OutputNState_Disable;
TIM_OCInitStructure.TIM_Pulse = 0x0FFF;
TIM_OCInitStructure.TIM_OCPolarity = TIM_OCPolarity_Low;
TIM_OCInitStructure.TIM_OCNPolarity = TIM_OCNPolarity_High;
TIM_OCInitStructure.TIM_OCIdleState = TIM_OCIdleState_Set;
TIM_OCInitStructure.TIM_OCNIdleState = TIM_OCIdleState_Reset;
TIM_OC4Init(TIM4, &TIM_OCInitStructure);
TIM_SelectOutputTrigger(TIM4, TIM_TRGOSource_OC4Ref);
/* TIM4 counter enable */
TIM_Cmd(TIM4, ENABLE);
/* TIM4 main Output Enable */
TIM_CtrlPWMOutputs(TIM4, ENABLE);
ADC_StartConversion(ADC1);
采集直流数据，采集变化非常大。采集值有100左右的变化。
另外，如果不添加ADC_StartConversion(ADC1);，采集是不会开始的，不知道哪里没有配置好。
差分，单极性，都试过，跳动非常厉害。比如，量程3V，输入电压1.6V，每200次采集平均滤波后，结果还在1.54~1.68V之间跳动。
我的目标是可以不准，毕竟可以校准的。但不能跳动，要稳。
模拟电源，参考电压，输入信号都稳定吗 一步步排查；
可以先接个标准的稳定信号先测试下，比如接电池 mmuuss586 发表于 2019-8-15 09:24
一步步排查；
可以先接个标准的稳定信号先测试下，比如接电池
是的，我的信号是电池。 输入V-=1.487V,V+=2.235V,参考=2.997V，部分采集值 理论上来说应该不会这样子。被测试的信号号是电池，还需要考虑参考电压是否稳定。再者就是芯片、参考地、被测试信号地，三者地线是否连接可靠。 不使用DMA ,单个通道ADC测试结果如何，先排队是硬件还是软件导致。 楼主的代码中DMA缓冲区长度是300*4，貌似分成4组对应4个差分通道，而ADC1与ADC2好像共用了这些缓冲区，看似ADC1与ADC2的数据重叠了。 xself 发表于 2019-8-15 09:38
不使用DMA ,单个通道ADC测试结果如何，先排队是硬件还是软件导致。
单通道采集同样的情况，能过确认的是外部电压是稳定的，没有变化。
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